From Taxonomy to Phylogenetics: Life and Work of Willi Hennig.— By Michael Schmitt.

Extract

The work of Willi Hennig brought about a paradigm shift in systematic biology by putting forward an approach to grouping species and lineages that in principle leads to reproducible and testable results (Farris 1979; Dupuis 1984; Schmitt 2003; Hall 2007; Wheeler 2008; Mishler 2009; Wiley and Lieberman 2011). Although Hennig's approach became quantitative and objective only after the development of computer algorithms by Farris (1970; also Kluge and Farris (1969), inspired by Herb Wagner's approach to grouping species, first shown in Hardin (1957)), it was Hennig (1949; also Hennig et al. (1953)) who had the crucial idea of contrasting plesiomorphic with synapomorphic and autapomorphic characters, who realized that synapomorphies could identify sister groups, and who put forward the concept of paraphyly, so essential to his insistence that only monophyla are worth studying and naming.

Hennig was born in Saxony in 1913 and died near Stuttgart in 1976. The occasion of his 100th birthday last year prompted several commentaries (e.g., Wheeler et al. 2013), as well as the book on his life and work by Michael Schmitt reviewed here. With 50 years of distance from the 1960s and 1970s, when the Hennigian revolution at times seemed close to causing heads to roll (Felsenstein 2001), it is interesting to learn about the content and context of Hennig's work from someone who has “read nearly every line Willi Hennig ever published, scanned scores of unpublished documents in private and public archives, and […] befriended Hennig's family” (Olivier Rieppel, in his blurb on the book's back cover).